Which ethical rule states that if an action cannot be taken repeatedly, it is not right to take at all? High-failure cost rule Lemming rule Golden Rule Slippery slope rule Utilitarian principle

The answer is to this question is Slippery slope rule

Explanation

The slippery slope rule is a rule that emphasizes on the need to carefully think a decision through before taking it because a relatively small first step leads to a chain of related events culminating in some significant (usually negative) effect .  It states that if an action  cannot be taken repeatedly, it is not right to take it at all.

Example of Slippery slope rule:

If you allow your children to choose the movie they want to watch, there is every tendency that they would want to continue in that trend i.e choosing what to watch.

However, if as a parent, you wont grant them the privilege to continue to choose what to watch, it is better not to allow them at all.